Enclosed cutout having a load break device



Jan. 21, 1958 s. R. SMITH, JR

ENCLOSED cuToEE HAVING A LoAD BREAK DEVICE 2 Sheets-Shea?l l Filed May 5, 1954 IMJWml/ A A wl Jan. 2l, 1958 s. R. sMrrH, JR

2,820,867 ENCLOSED CUTOFF HAVING A LOAD BREAK DEVICE` 2 Sheets-Sheet. 2

Filed May 5, 1954 United States PatentO CUTOUT HAVING A LOAD BREAK DEVICE Sidney R. Smith, Jr., Stockbridge, Mass., assigner to General Electric Company, a corporation of New York ENCLOSED 8 Claims.

'This invention relates to an enclosed cutout having a load break device, and more particularly, to an enclosed fused cutout having a manually operable door mounted load break device.

lt is an object of this invention to provide an enclosed cutout with a reliable, low cost, uncomplicated, and safe load break dev-ice.

My invention comprises an enclosed cutout having a manually operable load break device comprising an electrical insulating material housing having two spaced metallic terminal contacts therein, an electrical insulating material door for .said housing, three metallic contacts carried by said do-or adjacent the interior thereof, a first `and second of said three contacts electrically interconnected by an automatically operable current interrupting means, a third of said three contacts and said first contact electrically engageable with said terminal contacts when said door is closed, a tubular electrical insulating material portion carried by said door adjacent the exterior thereo-f, a manually operable movable spring driven metallic contact in said tubular portion electrically bridging said second and third contacts.

My invention further comprises an enclosed fused cutout having a load break device comprising an electrical insulating material housing having two spaced metallic terminal contacts therein, an electrical insulating material door for said housing, three spaced metallic contacts carried by `said door adjacent an interior thereof, a fuse link electrically interconnecting a iirst and second of said three contacts, said first contact and a third of said three conta-cts electrically engageable with said terminal contacts when said door is closed, a tubular electrical insulating material portion carried by said door adjacent an eX- terior thereof, a pair of spaced metallic contacts in said tubular portion electrically connected to said second and third contacts, an electrical arc extinguishing gas generating electrical insulating material sleeve in said tubular portion between said pair -of spaced contacts, a movable rod-like metallic contact within said sleeve electrically bridging said p-air of spaced contacts whereby an electrical circuit is established between said terminal contacts when said door is closed, an electrical arc extinguishing gas generating electrical insulating material rod-like member connected at one end thereof to one end of said rod-like contact and comprising a continuation of said rod-like contact, a piston connected to another end of said rod-like member and said rod-like member and piston positioned within said tubular portion, a manually releasable tensioned spring bearing against said piston wherein release of said tensioned spring causes replacement of said rodlike contact with-in said sleeve by said rod-like member whereby said electrical circuit can be manually interrupted without opening `of said door.

The features of my invention which I believe to be novel are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation, together with further 7objects and advantages thereof, may best be understood "ice 2 by reference to the following description taken in connection with the accompanying drawings.

In the drawings, Fig. 1 is a side elevation view, partly in section, of one form of my invention. Fig. 2 is a top view of the door of said one form of invention. Fig. 3 is a partly broken away perspective view of said one form of invention after the load break device thereof has been tripped. Fig. 4 is a side elevation view, partly in section, of another form of my invention. Fig. 5 is a 4top View of said another form of invention. Like reference numerals will be used throughout the various figures to indicate identical parts.

Referring now to the drawings, and more particularly to Fig. l, shown therein is one form of my invention com prising an electrical insulating material or porcelain housing 1. Positioned within housing 1 is a pair of spaced upper and lower metallic terminal contacts 2 and 3. Housing 1 is closed by an electrical insulating material door 4. Door 4 is hinged to housing 1 by virtue of a generally U-shaped fuseholder lower metallic Contact hinge member 5 hooked on to a pair of bearing members 6. See also Fig. 3.

Carried by the door 4 adjacent the interior thereof is an electrical insulating material fuseholder or fuse tube 7. The upper end of fuseholder 7 is closed by an upper fuseholder metallic contact 8. Disposed between the upper and lower fuseholder contacts 8 and 5 is another fuseholder metallic contact 9.

The fuseholder 7 is disposed between a pair of electrical insulating material latching arms 10 integral with door 4. Latching arms 10 are adapted to be engaged by a pair of spring latching lingers 11, onlyone of which is shown, to hold the door 4 closed. As will be more clear hereinafter, the generally U-shaped fuseholder lower contact hinge member 5 is fastened to the interior of door 4. A pin 12 extends through the leg portions of U-shaped member 5 and is disposed within a tangentially extending groove formed in an outer circumferential portion of the fuseholder 7 to hold the fuseholder 7 axially immovable. The upper end yof fuseholder 7 ycan be steadied with respect to the door 4 as by mechanically fastening the'upper fuseholder contact 8 to the door 4 by screws or the like.

Disposed within the fuseholder 7 is a fuse link 13 connected at its opposite ends to the upper and lower fuseholder contacts 8 and 5. The lower end of fuse link 13 can be electrically connected to the lower fuseholder contact 5 as by mechanically fastening said lower fuse link end to the base portion of U-shaped member 5 by a thumb screw or the like. As will be clear from Figs. l and 3, the lower end of the fuse link 13 passes around a spring biased flipper arm 14.

When the door 4 is closed the contacts 8 and 9 make electrical engagement with the terminal contacts 2 and 3. As will be more clear hereinafter, fuse link 13 cornprises part `of an electrical circuit established between the terminal contacts 2 and 3. The interior of the fuseholder 7 is adapted to evolve an electrical arc extinguishing gas when subjected to an electrical arc or the heat thereof. Accordingly, as will be obvious to those skilled in the art, when an overcurrent occurs in the fuse link 13 the fusible portion thereof will be ruptured and the flipper arm 14 will extract the lower ruptured end of the fuse link 13 from within the fuseholder 7. Thus, flipper arm 14 causes elongation of the electrical arc established between the ruptured ends of fuse link 13, and the electrical arc extinguishing gas generated by the interior of fuse-` holder 7 in conjunction with said elongation extinguishes 'the electrical arc between the ruptured ends of 'fusey link 13.

Integrally formed in the exterior of door 4 is atubularr electrical insulating material portion 15 having a cylindrical bore 16 therein extending gene-rally parallel to the fuseholder 7. The lower fuseholder contact is connected to another metallic U-shaped member 17` which in turn is connected to the interior of door 4 by a metallic screw 18 or the like. Screw 18 protrudes into the cylindrical bore 16 and is also connected to an arcuate metallic contact shoe `19.

. Fuseholder` contact `9 is connected to the interior of door 4 by a metallic screw 20 or the like. Screw 20 protrudes into the cylindrical bore 16 and is also connected to another arcuate metallic contact shoerZl likewise disposed within the cylindrical bore 16. An electrical arc extinguishing gas generating electrical insulating material inner liner or sleeve 22 is disposed within the tubular portion 15, between `the two spaced arcuate contact shoes 1.9 and .21.

Disposed within the cylindrical bore 16 is a spring driven rod-likemember. Approximately the upper half 23 of said rod-like member is constructed out of an electrical are extinguishing gas generating electrical insulating material. y The approximately lower half 24 of ,said rod-like member is constructedrout of metallic electrical conducting material.v '1" he bore of sleeve 22 has a slightly larger inner diameter than the outer diameter of rod 23, 24. Connected to the` lower en d of conducting material 24 is an electricalinsulating material knob 25. In the Fig. l position of the. device, conducting material 24 is disposed within the liner or sleeve 22 and electrically bridges the n arcuate contact shoes 19 and 21 whereby an electrical circuit is established between terminal contacts 2 and 3 through contact 8, fuse link 13, contact 5, U-shaped member 17, screw 18, contact shoe 19, conducting material 24, contact shoe 21, screw 20, and'contact 9.

n AThe upper end of electrical arc extinguishing gas gen* erating material 23 has a piston 26 connected thereto. Diso posed between piston 26 and the upper closed end of tubular portion is a compressed spring 27. Spring 27 continuously biases the rod-like member 23, 24 for downward movement out of the lower open end of tubular portion 1S. Said downward movement is limited by engagement of piston 26, with the upper arcuate contact shoe 21.

Disposed about the lower arcuate contact shoe 19 is a metallic contact spring 28 biasingfthe rod portion 24 into intimate contact engagement with'the lower arcuate contact shoe 19. The upper arcuate contact shoe 21 has a similar metallic contact spring 29. However, a portion of contact spring 29 is purposelylpositioned longitudinally below the upper arcuate contact shoe 2,1 whereby when therod portion 24 moves downwardly an electrical arc will be drawn between spring 29 and portion 24 instead of between contact lshoe l21* and portion 214 whereby the contact shoe 21 will not be subjected to electrical arcing there byprolonging its life.

Integrally formed with the doorL 4 and tubularportion 15 is` an electrical insulating materialhandle 30. A longitudinal slot`31, see Fig. 2, is formedin handle 30 and in said longitudinal slot 31 is positioned a releasable spring dr1venmetallic LJ-shaped` latching'elernent 32'. y The upper end` oli latching element 372 is connected to a fixed pivot 40, and the lower end-` of latchingelment 32 has a. latching tooth` 41x01" the like formed thereon. Said latching tooth 41 protrudesv into the cylindrical bore 16 below piston 26 Ywhen the rod-like member 2.3, 24 is in its upper most position illustrated in Fig. l. `Upward travel of the spring driven rod-like member 23, `24 is limited by engagement of knob." 2,5,- with thelower arcuate contact shoe 19. lt will be. noted, that in the Fig.. lposition of my; device .there are no exposed metallic parts. For instance, metallic latching element'. 32 is-enclosed by electrical insulating material handle 30, and metallic portion 24isvdispolsed within electrical insulating material tubular portion 15. Accordingly, my invention provides safety'precautions for the operator orlineman by having a' minimumexposure of metallic parts.

As will be obvious to those skilled in the art, the elecd trical circuit of the fused cutout can be manually interrupted by pivoting the door 4 open. However, such a procedure for breaking the load may result in heavy electrical arcing between the terminal contacts 2 and 3 and the fuseholder contacts 8 and 9. Said heavy electrical arcing tends to damage the cutout parts, endangers the safety oi the operator or lineman, and may result in a major short circuit. In my invention, the aforementioned disadvantages of manually interrupting the load are substantially avoided in a reliable, low cost, uncomplicated, and safe manner. To interrupt the load, the hook of a switch stick or the like is inserted in the eye of handle 30. An outward pull on the latching element 32 will release the spring driven rod-like member 23, 24 for downward movement by the tensioned spring 27. As the rod-like member 23, 24 moves downwardly, an electrical arc is drawn between contact spring 29 and conducting material portion 24. Said electrical arc is drawn within the annular bore defined by the interior surface of liner or sleeve 22 and the exterior surface of rod-like members 23 24. With said arc disposed in said annular bore, electrical arc extinguishing gas generating materials 22 and 23 will evolve an electrical are extinguishing gas. Said gas and elongation of the electrical arc by continued downward movement of conducting material portion 24 with respect to the contact spring 29 will result in extinguishment ol' said arc and interruption of the electrical circuit between terminal contacts 2 and 3. Final downward movement of rod-like member 23, 24 is arrested when the piston 26 engages the upper arcuate Contact shoe 21. ln this position of the device, the parts will be in the positions shown in Fig. 3. To make the load or re-establish the electrical circuit between terminal contacts 2 and 3 an operator or lineman need only drive the rod-like member 23, 24 upwardly until the piston 26 is latched against downward movement by the `latching tooth of latching element 32. Also, it will be noted my invention provides aload break device wherein the loadbreak operation may be accomplished in one operating movement. All an operator need dois insert the hook of a switch stick in the eye of handle 30 and pull outwardly as if he were opening a conventional enclosed cutout door. Additionally, by pulling outwardly on the switch stick sutlic'iently the door 4 can be simultaneously opened to disengage the fuseholder 7 from the terminal contacts 2 and 3 within the same single load break operating movement.

Referring now to Figs. 4 and 5, shown therein is another form of myl invention. Said another form of invention is identical to the 'first form of invention except that the electrical'insulating-'material door 4 is a conventional enclosed cutout doorl Also, the electrical insulating material tubular Vpdrtion 15 isa vseparately formed member removably fastened to the exterior of door 4. The piston 26 has a lost motion'connection with the upper end of the electrical insulating material rod-like portion 23. Disposed at the uppermost end of electricalinsulatingmatcrial. Yportion 23 isa stop member or'washer 4 2. Disposed between'saidstopmember or washer' 42 and the piston 26 is a spring 33 whereby' when spring 27 drives piston 26' downwardly, piston 26 will resiliently bottom against the not shown upper arcuate metallic contact shoe Within the tubular` portion 15. The Upper end of tubular portion 15 is closed by' a closure-capr34, and tosaid closure cap 34 ispivoted'a U-shapedspring driven handle 35. The-lower endy of'handle. 35 has a losti motion connection with a stationary pin 36' or the-'likewhereby the handle 35 is also utilized as thellatchin'g element for pisto'n'26.

Both forms of myinvention provide a fuseholder and load break device doorwhichf can be usedwitha conventionall enclosed cutouth'ou'sing. Thus, at cutout installations requiring frequent and severe switching duty one 'of my fusehold'er and load' break device doors can be used with the conventional enclosed cutout housing. In other tutout installations requiring less frequent and severe switching duty a conventional fuseholder door may be sucient, or the conventional fuseholder door can be temporarily replaced by one of my fuseholder and load break device doors during the switching period.

While there have been shown and described particular embodiments of the invention, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention, and that it is intended by the appended claims to cover all such changes and modifications as fall within the true spirit and scope the invention. What I claim as new and desire to secure by Letters Patent of the United States is:

l. An enclosed cutout having a load break device comprising an electrical insulating material housing having two spaced metallic terminal contacts therein, an electrical insulating material door for said housing, current interrupting means on said door for completing an electrical circuit between said terminal contacts when said door is closed, said current interrupting means having three spaced metallic contacts, a first and second of said three current interrupting means contacts electrically inter-connected by said current interrupting means, a third of said three current interrupting contacts and one ofsaid first and second contacts electrically engageable with said terminal contacts when said door is closed, a tubular electrical insulating material portion on said door, a movable spring driven metallic contact in said tubular portion electrically bridging said third contact and the other of said first and second contacts.

2. An enclosed cutout having a manually operable load break device comprising an electrical insulating material housinghaving two spaced metallic terminal contacts therein, an electrical insulating material door for said housing, three metallic contacts carried by said door adjacent the interior thereof, a rst and second of said three contacts electrically interconnected by an automatically operable current interrupting means, a third of said three contacts and said first contact electrically engageable with said terminal contacts when said door is closed, a tubular electrical insulating material portion carried by said door adjacent the exterior thereof, a manually operable movable spring driven metallic Contact in said tubular portion electrically bridging said second and third contacts.

3. An enclosed cutout having a load break device comprising an electrical insulating material housing having two spaced metallic terminal contacts therein, an electrical insulating material door for said housing, three metallic contacts carried by said door adjacent an interior thereof, a first and second of said three contacts electrically interconnected by an automatically operable current interrupting means, a third of said three contacts and said first contact electrically engageable with said terminal contacts when said door is closed, an electrical insulating material tubular portion carried by said door adjacent an exterior thereof, a pair of spaced metallic contacts in said tubular portion electrically connected to said second and third contacts, an electrical arc extinguishing gas generating electrical insulating material liner in said tubular portion between said pair of contacts, a movable metallic contact within said liner electrically bridging said pair of contacts whereby an electrical circuit is established between said terminal contacts when said door is closed, and a manually releasable tensioned spring for moving said movable contact whereby said electrical circuit can be manually interrupted without opening of said door.

4. An enclosed fused cutout having a load break device comprising an electrical insulating material housing having two spaced metallic terminal contacts therein, an electrical insulating material door for said housing, three spaced metallic contacts carried by said door adjacent an interior thereof, a fuse link electrically interconnecting a first and second of said three contacts, said first contact and a third of said three contacts electrically engageable with said terminal contacts whenl 'said door is closed, an electrical insulating material tubular portion carried by said door adjacent an exterior thereof, a pair of spaced metallic contacts in said tubular portion electrically connected to said second and third contacts, an electrical arc extinguishing gas generating electrical in sulating material sleeve in said tubular portion between said pair of spaced contacts, a movable rod-like metallic contact within said sleeve electrically bridging said pair of spaced contacts whereby an electrical circuit is established between said terminal contacts when said door is closed, an electrical arc extinguishing gas generating electrical insulating material rod-like member connected at one end thereof to one end of said rod-like contact and comprising a continuation of said rod-like contact, a piston connected to another end of said rod-like member, said rod-like member and piston positioned within said tubular portion, a manually releasable tensioned spring bearing against said piston wherein release of said tensioned spring causes replacement of said rod-like contact within said sleeve by said rod-like member whereby said electrical circuit can be manually interrupted without opening of said door.

5. A fuseholder and load break device electrical insulating material door, said door having an electrical insulating material fuseholder positioned `on one side thereof, a metallic contact at one end of said fuseholder and a metallic hinge member adjacent another end of said fuseholder, a fuse link within said fuseholder electrically connected at opposite ends thereof to said one end contact and said hinge member, another metallic contact dis posed on said one side between said one end contact and said hinge member, an electrical insulating material r tubular portion on another side of said door, said tubular portion and said fuseholder extending generally parallel to each other, a pair of spaced metallic contacts in said tubular portion opposite to said another contact and said hinge member and electrically connected thereto, and a releasable and resettable spring driven metallic contact within said tubular portion electrically bridging said pair of contacts to alternately break. and make an electrical circuit between said one end contact and said another contact.

6. A combination fuseholder and load break device electrical insulating material door adapted to close an electrical insulating material housing and complete an electrical circuit between two spaced metallic terminal contacts disposed within said housing, said door having an electrical insulating material fuseholder at one side thereof, a metallic contact at one end of said fuseholder and a metallic hinge member adjacent another end of said fuseholder, a fuse link within said fuseholder e1ectrically connected at opposite ends thereof to said one end contact and said hinge member, another metallic contact on said one side disposed between said one end contact and said hinge member, said one end and another contacts adapted to electrically engage said terminal contacts when said door is closed with respect to said housing, an electrical insulating material tubular portion on another side of said door, a pair of spaced metallic contacts within said tubular portion opposite to said another contact and said hinge member and electrically connected thereto, and a manually operable movable spring driven releasable and resettable metallic contact disposed within said tubular portion electrically bridging said pair of contacts whereby said electrical circuit can be broken and made when said door is closed within said tubular portion substantially without any exposed electrical arcing.

7. In an electrical insulating material door for an enclosed fused cutout, an electrical insulating material fuseholder positioned on said door adjacent an interior thereof, said fuseholder having an upper and lower metallic contact thereon, a fuse link in said fuseholder connected at opposite ends thereof to said upper and lowerl contacts', another metallic contact adjacent: said interiorrdisposed betweensaid upper and lower contacts; af cylindrical` bore formed Vin an integral: exterior electrical insulating material Vportion of said door extending generallyfipa'rallelto said fuseholder, a pair of spaced metalliccontacts in said bore disposed opposite toV said lower and another contacts and electrically connected thereto, an upper end'of said bore being closed and a lower end of saidbore being -open, an electrical arc extinguishing gasgenerating electrical insulating material sleeve within said;` boref between said pair of` spaced contacts, a movable rodllike member within said bore, an approximate lower half of said rod-like member composed of electrical 'conductingmaterial disposed within said sleeve and electrically bridgingsaidpair of spaced contacts whereby an: electrical circuit is established between said upper andanotiier contacts, an.` approximate upper half of said rod-like'membercomposed of electrical arc extinguishing gasrgenera'ting electrical insulating material, a piston on an,upper'end'ofy s'aid'rod-like member, a tensioned spring between: said closed` bore end and said piston biasing saidrroddike member for movement out of said open bore end, a manually releasable latch restraining said movement'wherebywhen said latch is released said upper half'displaces said lower yhalf within said sleeve to interrupt said electrical circuit.

8. Inan electrical insulating material door for an enclosed tuse'dfcutout, an electrical insulating material fuseholder. positioned on said door adjacent an interior thereof, said 4fusefnolder having an` upper and lower metallic contactthereon, a `fuse link in said fuseholder connected at oppositeends thereof to said 'upper and lower contacts, another metallic Contact adjacent said interior disposed between said 'upper' and lower contacts, an electrical insulating material tubular member removably fastened to said door "Jd'j'ac'e'nt'ah exterior thereof, said fuscholder and tubular'me'mberextending generally parallel to each other, 'a p'air of spaced metallic contacts within said tubular vmember disposed opposite to said lower and another contacts and electrically connected thereto, an electrical arc extinguishing; lgas generatingelectrical insulti-f;

ing material Isleeve withinsaid tubular portion betweensai-d.. pair of spaced contacts, arod-like-memberrpositionod within said tubular. member, anapproximate lower half. of said rodflike member composed of electrical conducting material positioned Within 'said'sleeve and electrically bridging said pair of spaced contacts to establish -an electrical circuit between. said upper land another contacts, an approximate upper half of said rod-like ymember com posed of electrical arc extinguishing. gas generating electrical insulating material, a piston on an upper end of said rod-like member having a resilient lost motion connection therewith, and a tensioncd spring between said piston and -a closed upper end of said tubular member biasing said rod-like member for movement out of a lower open end of said tubular member, said movement limited by resilient engagement of sadrpiston wit-h an upper one of `said pair of lspaced contacts, and amanually releasable latch restraining said movement whereby when said latch is released said upper half displaces said lower half within said sleeve to interrupt said electrical circuit.

References Cited i-n the tile of this patent UNITED STATES PATENTS 826,888 Sachs July 24, 1906 y1,393,344 Conrad Oct. 11, 1921 2,150,249 Sanford Mar. 14, 1939 2,204,309 Carlisle f June 11, 1940 2,249,662 Matthews July 15, 11941 2,256,232 Bennett Sept. 16, 1941 2,272,717 Ludwig et al. Feb. l0, v1942 2,344,113 Schultz Mar. 14, 1944 2,438,746v Garrison Mar. 30, 1948 2,526,201 Daly Oct. 17, 1950 2,636,955 George Apr. 28, 1953 2,671,142 Lindell Mar. 2, 21954 2,709,736 Schneider May 31, 1955 2,716,681 Smith Aug. 3'0, 1955 2,734,966 Schneider Feb. 15, 1956 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NQ, 2,820,867

Sidney lit is hereby certified th requiring Oorecon and that the reeted below,

r 1n the drawings sheets 1 and P "ENCLQSED CUTOFF HAVNG A LOAD A LOAD BREAK DEVCE m-o at error appears in tle above numbered pa-,Ont said Letters ate'nt lsh Ould read. as corn y line 2;, title o nvanton, for

AK DEVCE read m ENCLOSED CUTOUT HAV'JNG Sigma@ and sealed this 6th day of 1%9.,

SEAL) test:

KARL H., XLINE Attesting Offier ROBERT c. WATSON Conmissioner of Patents UNITED STATES PATENT OFFCE CER'IIFICATE 0F @ERECTION Patent NO 22,820,867 January 2l, 1958 I Sidney R, smith, Jr;

' It, is hereby certified that error appears in the above numbered patent requiring Correction and that the said `Lettere Patent lshould read as eor= rected belowo e v the drawings, Sheets l and 2, line Q title of mren:ien9 for "ENCLOSED CTOFF HAVING A LOAD BREAK DEVCE read ENCLGSED CTOLT EAVNG A LOAD BREAK DEVISE =H= Y Signed end sealed this 6th iz-1y of Jennery 1959,

SEAL) ttset:

KARL H., MINE A ROBERT c. wATsoN tteting Officer Conmissioner of Patents 

